Dynamic exposure metering based on face detection

摘要

A system, computer readable medium, and method for dynamically setting a camera's exposure parameters based on face detection are disclosed. When taking a picture or video of a person in front of a bright background, standard exposure algorithms tend to overexpose the background. In one embodiment disclosed herein, a face detection algorithm is run on the current picture or video frame, and the exposure metering region is inset over the detected face. Exposure time, gain, or other exposure parameters may be set based on the pixels within the exposure metering region. In another embodiment, the exposure metering region tracks a moving face according to lag parameters so that the exposure metering region remains substantially over the face. In yet another embodiment, a plurality of faces may be tracked, with the exposure parameters set based on a weighted average of the pixels within the plurality of face-containing exposure metering regions.